Method and apparatus for utilizing and burning anthracite dust coal and the like



June 5. 1928. 1,672,405

F. G. BREYER METHOD AND APPARATUS Eon UTILIEING AND BURNING ANTHRACITE nusT coAL AND THE LIKE I N VEN TOR.

A TTORNEYS.

June 5, 1928.

F. G. BREYER IN VEN TOR.

2 Sheets-Sheet f... 4., BY @u .rw n@ ATTORNEYS.

Filed June 6. 1927 ANTHRACITE DUST COAL AND THE LIKE METHOD AND APPARATUS FOR UTILIZING AND BURNING Patented June 5, 19287 UNITED STATES PATENT OFFICE.

I'BANX G. BREYER, OF BRONXVILLE, NEW YORK, ASSIGNOB OF ONE-HALF T0 J'. A. BINGMASTER, 0F NEW YORK, N. Y.

IETHOD AND .APPARATUS FOR UTILIZING AND BURNING ANTHRACITE DUST COAL AND THE LIKE.

Application led .Tune 6,

This invention relates to the combustion of finely divided combustible material for heating and steam generating purposes and for the generation of gas, and is particularly applicable to the economical burning and utilization of fine anthracite dust or dirt coal for these indicated purposes.

Up to the present time the burning of such fine anthracite dust or dirt coal for power purposes and for generating gas has not been successful. It cannot be economically burned on grates, either stationary or mechanical, because it is impossible to get a suicient volume`of air through the bed for economical combustion Without blowing holes through the bed, through which the air rushes, leaving adjacent areas of fuel unburned. The coal is so fine and the interstitial spaces are so small as to set up a frictional resistance which simply does not `permit the even flow of the requisite volume of air through the bed on the grate. Nor can anthracite dust or dirt be economically burned in pulverized coal burning equipment. This is largely because anthracite coal burns slowly if the coal particles are of any size, While on the other hand if the anthracite is crushed very line, much finer than bituminous coal has to be crushed to burn in pulverized coal burning equipment, it will urn satisfactorily but the cost of such crushing is excessive. Moreover the bulk of the anthracite fine coal now available on the dumps and currently produced, has such a high ash content, very much higher than bituminous coal for similar urposes, that it must first be mechanically concentrated, floated, or the like to rid 1t of the larger portion of the ash forming constituents, slate, clay, etc. before it can be used for firing in powdered form. Concentrating as ordinarily practiced on anthracite dust coal adds not only to the cost of preparation, but results in considerable losses of combustible matter carried off with the ash. In addition the anthracite flame is short and is so very hot, that it is diiiicult of control and excessively scorifyngl on the brick work of the combustion chambers.

It has been pro osed to briquet fine anthracite coal and urn it under boilers but the cost of briquetting and utilization acg oording to prior practice has more than out- 1927. Serial N0. 196,719.

balanced the difference 'in cost between dust coal and the coarser steam sizes such as #1, 2, 3 buckwheat coals which can be success; fully burned on traveling grate types of stokers. In the practice of briquettin fine fuel for use in boiler and gas furnaces 1t has been assumed that the briquettes must be made quite strong and capable of maintainmg their form indefinitely, and accordingly elaborate and expensive briquettin methods have heretofore been em loyed, inc uding the use of large quantities o binders and of special baking and curing operations. Moreover, much thought and expense have been involved in maklng such briquettes water-YV proof, inasmuch as a reserve suppl of briquetted fuel had to be kept on handy; to take care of possible breakdowns in the briquetting plant, and this large reserve supply had to be handled and stored.

According` to my invention I entirely avoid the expenslve and uneconomical crushing, purifying, concentrating and briquetting operations heretofore practiced in the burning and utilization of fine anthracite dust or dirt coal in the generation of steam, and I effect this hy feeding the natural untreated, unpm-ilied and non-briquetted anthracite dust or dirt directly to the front end of the boiler furnace combustion chamber and upon the moving grate and in the form of agglomerates or compressed masses of loosely adhering particles of suitable shape and sufiicient size to permit and facilitate the passage of an even and uniformly distributed blast of combustion supporting air and steam up through the ag lomerated masses or compressed anthracite bed, the agglomerates being formed in continuous operation during the passage of the fuel dust to the furnace and the extreme nes contained in the anthracite dust being utilized to hold it together in the form of the agglomerates from the time they leave the agglomerating deair through the bed of agglomerate anthracite dust to form combustion gases (CO and H) and by admitting thereabove air for supporting t e combustion of the combustion ases, I am able to obtain a long bituminouscoal-like ame from the burning ofthe anthracite dust or dirt and in a particularly economical manner. The agglomerates being green when fed to the furnace, the combustion chamber forms a combined drying, and combustion space therefor. The agglomerating device must be capable of re ceiving the reen untreated anthracite dust or dirt and orming agglomerates thereof 0r masses of loosely adhering particles as by mechanical compressing operations, and Suc 1 device preferably also forms the regulating means for supplying the required quantity of coal dust to the furnace in accordance with the demands of the steam generation, this latter function being obtained as for example by varying the speed of the agglomerating device.

For a better understanding of the inven` tion, reference may be had to the accompanying drawings illustrating an apparatus for practicing the same, Wherein,-

Fig. 1 is a diagrammatic view partly in sectional elevation illustrating the application of my invention to the generation of steam, Fig. 1a is a diagrammatic front view of this apparatus with certain parts removed, and

Fig. 2 is a diagrammatic view partly in section of an apparatus illustrating the application of my invention to the production of gas.

Referring to Fig. 1 of the drawing, I have indicated a steam boiler 1 disposed at one end of an elongated combustion chamber2 of a suitable boiler furnace having an arch roof indicated at 3 and an arch 4 at the end of the combustion chamber opposite the boiler 1. The side wall of the furnace is provided with openings 5 leading from the outside into the combustion chamber 2 for a purpose hereinafter set forth. I have indicated diagrammatically a moving grate 6 passing from the front end of the combustion chamber 2 to and under the boiler 1, this grate being of any standard construction and carried by drums indicated at 7. The grate 6 is adapted to receive and carry a bed of anthracite fuel 8 extending from the front end of the combustion chamber 2 to the rear end thereof underneath the boiler 1, the top line of the bed of fuel being indicated by the broken line 8', and the bed being indicated as gradually decreasing in depth towards the rear end, a suitable dump 9 being indicated for receiving the ash after the complete combustion of the anthracite by passing through the combustion chamber 2. I have indicated at 10 any suitable means for supplying the anthracite dust or dirt coal 11, and at 12 I have indicated diagrammatically an agglomerating device or apparatus disposed between the feeding means 10 and the front end of the combustion chamber 2 of the furnace. the device or apparatus 12 being capable of recciving the anthracite dust or dirt coal 11 and forming agglomeraties thereof of snitable shape and sufficient size to form the required character and permanence ot' fuel hed 8 upon the grate (i. From the device or apparatus l2 the anthracite dust, which is now in the form of agglomerates or masses 'i3 of loosely adhering particles. is delivered to a laterally inclined belt-conveyor 14. the latter running along in front ot' the boiler furnace and above the level of the grate ti so as to permit the agglomerates lil to be conveyed by gravity to the front end ot the combustion chamber 2 underneath the arch 4 and upon the front end of the moving grate 6. The conveyor 14 is indicated as laterally inclined downwardly toward the front end of the furnace so as to cause the agglomerated anthracite dust to readily slide oil', and a gravityslide or chute 15 is indicated for guiding the anthracite dust in the form of the agglomcrates from the con veyor to the grate underneath the arch 4. The slide or gravity chute 15 may he perfo` rated for a portion of its length to permit the passage therethrough of fines and agglomerated parts of unsuitable dimensions` for the bed 8, which fall down through a chute 16 having a fia ring opening or mouth immediately below the perforated part of the gravity slide 15. The agglomerating device or apparatus 12 may be of any suitable character, but preferably consists of compression rollers of a shape and form to receive and form the anthracite dust into the desired agglbmerates by pressure operations, fines contained in the anthracite dust being utilized to hold and maintain the agglomerated material in the agglomerated form during the passage from the device 12 to and through the combustion chamber 2. The device or apparatus 12 is preferably also of a character to enable the quantity of fuel to be supplied to the boiler furnace to be varied at will or according to the demands of the heilen-as for example by a variation in speed of the rollers. The details of the device 12 are omitted for convenience in illustration. I have indicated in Fig. 1n this device 12 as including a hopper 31 and a pair of rollers 32.

Underneath the moving grate 6 with the fuel bed 8 thereon, I have indicated a chamber 17, the bottom and end walls of Which are indicated respectively by the numerals 18 and 19. Into this chamber leads a blast pipe or conduit 20 for the supply of a suitable blast of combustion supporting air, as for example a forced draft as generally employed in boiler furnaces. I have also indicated diagrammatically as leading into this blast conduit 20, a steam supply line 21, and by this arrangement a suitable quantity of steam may. if desired. be' introduced into the blast of combustion supporting air entering the chamber 17 and 'caused to pass therewith up through the grate 6 and the fuel bed 8 of anthracite dust agglomeraties. By reason of the agglomerated character of the anthracite bed 8, the air and the steam are permitted to pass therethrough in a uniformly distributed manner throughout the length and breadth of the fuel bed 8 and to thereby effect complete combustion and utilization of the energy of the anthracite dust. The admission of the steam and passage of the same with the combusting air up through the anthracite fuel bed 8 produces the combustion gases CO and H, the combustion of which gases within the combustion chamber 2 is .supported by air admitted through the side openings 5 above the fuel bed 8, and a long heating flame is thereby obtained from the anthracite fuel and in a particularly economical manner. The only treatment to which the anthracite dust or dirt 11 has been subjected in its passage to the front end of the combustion chamber 3 of the furnace is the agglomerating of the same in the passage through the apparatus 12. The necessity for briquetting with the attendant elaborate and expensive operations is entirely obviated, and in the preferred practice the anthracite dust is used as it comes from the mines without concentration or y urification.

Ordinari y in practice the green anthracite dust agglomerates are assed from the conveyor 14 to the front en of the combustion chamber 2 underneath the furnace arch 4 without any intermediate drying or curing operation, and accordingly the front end of the combustion chamber 2 serves as a combined dryin and combusting chamber. It is understoo however, that if desired, waste gases or other drying or heating means may be passed through the anthracite dust agglomerates as they pass down the gravity slide or chute 15, upon the grate to partially dry them before they reach the combustion chamber. It is also understood that suitable conveyors may be provided for conveying the fines, etc. dropping down the chute 16 back to the supply of anthracite dust or dirt coal. Ordinarily I prefer to form the agglomeraties of the natural untreated anthracite dust and with the addition of no binder thereto, but it may be desirable in certain cases to add a small quantity of binder to the dust 1l to assist the fines contained therein in holding the fuel in the agglomerated form. Agglomerates as large as from three to six ounces formed without addition of a binder hold their form sufficiently while passing through the combustion chamber to maintain the desired character of bed 8, namely a bed through which a strong blast of air and steam may be evenly and uniformily diffused without the formation of blow holes, etc.

I have shown in Fig. 1 only one boiler and furnace of a bank of two or more, all of which may be fed by the same conveyor 14 disposed and running in front thereof.

In Fig. 2 I have indicated an apparatus for the production of gas. In this case the furnace has an arch roof 25, an end wall 26 and front arch 27 and is otherwise entirely enclosed except for the outlet 28 for the gas or gases produced, the outlet 28 being near the front end of the furnace. The apparatus otherwise is identical With the apparatus of Fig. 1 except that since the potential energy contained in the solid coal is to be converted to potential heat energy in the gases C() and H, a larger quantity of steam must be admitted with the air, and accordingly the steam inlet 21 must be capable of delivering a sufficient quantity of steam for this purpose. The operation and functioning of the apparatus is substantially the saine as described in connection With Fig. l. the anthracite dust or dirt ll beine' agglomerated by passing through the device or apfparatus 12 and from there delivered in the orm of agglomerates to the moving grate 6 passing through the combustion chamber of the gas furnace. By agglomerating the anthracite dust 11 and introducing it directly upon the grate 6 into the form of the moving bed 8, the air and steam admitted into the chamber 7 are permitted to be uniformly diffused throughout the bed 8 during their passage therethrough and the potential energy of the anthracite dust is thereby economically converted into otential heat energy in the gases delivered through the outlet 28. A strong blast of air and steam may be forced through the bed 8 Without the production of blow holes, the resistance to passage therethrough being substantially uniform and even throughout the bed.

I claim:

1. The method of utilizing anthracite coal dust and the like in steam boiler and gas producer furnaces of the traveling grate type comprising, in a continuous operation, compressing the dust into masses of loosely adhering particles, feeding the masses directly to the furnace and burning the same therein.

2. The method of utilizing` anthracite coal dust and the like in steam boiler and gas producer furnaces of the traveling grate type which comprises forming said dust into masses of loosely adhering particles bv pressure, feeding the masses so formed directly into a furnacein continuous operation, and burning said masses therein.

3. The method of utilizing anthracite coal dust and the like in steam boiler and gas producer furnaces of the traveling grate type which comprises in continuous operation compressing said coal dust into masses lll of loosely adhering particles and of such size and shape that a bed of these masses is uniformly and amply porous to combustion gases, feeding the masses so formed directly from the compressing device into the furnace, and progressively passing a bed thereof through the furnace icombustion chamber While passing a draft of combustion supporting air up through the progressively moving bed.

4. The method of utilizing anthracite coal dust and the like in steam boiler and gas producer furnaces of the traveling grate type comprising, in 4a continuous operation, compressing the dust into green masses of loosely adhering particles, feeding said masses directly from the compresslng device to and through the combustion charnber of the furnace where they are first cured and then combusted and while the masses are moving through the combustion chamber, passing a forced draft of combustion supporting air evenly and uniformly through the hed.

5. The method of utilizing anthracite coal dust and the like in steam boiler and gas producer furnaces of the traveling grate type which consists. i.' continuous operation, of compressing the dust into masses of loosely adhering particles, feeding the masses directly from the compressing device to a traveling grate furnace and progressively passing a bed thereof through the furnace combustion chamber and forcing a draft of air and steam up through the progressively moving bed of compressed masses and sup plying air above the bed to support combustion of the gases formed.

G. The method of utilizing anthracite coal dust and the like in steam boiler and gas producer furnaces of the traveling grate type which comprises, in a continuous opera. tion, compressing the fine fuel into masses of loosely adhering particles, passing these masses directly and continuously from the compressing means to and through the combustion chamber of the furnace and utilizing the compressing means to regulate the quantity of coal dust masses supplied to the furnace.

In testimony whereof, I have sig'ied my name to this specification.

FRANK G. BREYER.

CERTIFICATE 0F CORRECTION.

Patent No. l, 672, 405.

Granted June 5, 1928, a'

FRANK G. BREYER.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as tollovrs: u strike out the words "masses or compressed anthracite bed, the agglomerates ai,

tead "anthracite hed, the agglomerates or compressed masses"; and that ith this correction therein that the sare:

insert ins the said Letters Patent should be read w Page l. lines 90 and 9;

may conform to the record of the case in the Patent Office. Signed and sealed this 3rd day of July, A. D. l92.

(Seal) M. J. Moore,

Acting Commissioner of Patr:

of loosely adhering particles and of such size and shape that a bed of these masses is uniformly and amply porous to combustion gases, feeding the masses so formed directly from the compressing device into the furnace, and progressively passing a bed thereof through the furnace icombustion chamber While passing a draft of combustion supporting air up through the progressively moving bed.

4. The method of utilizing anthracite coal dust and the like in steam boiler and gas producer furnaces of the traveling grate type comprising, in 4a continuous operation, compressing the dust into green masses of loosely adhering particles, feeding said masses directly from the compresslng device to and through the combustion charnber of the furnace where they are first cured and then combusted and while the masses are moving through the combustion chamber, passing a forced draft of combustion supporting air evenly and uniformly through the hed.

5. The method of utilizing anthracite coal dust and the like in steam boiler and gas producer furnaces of the traveling grate type which consists. i.' continuous operation, of compressing the dust into masses of loosely adhering particles, feeding the masses directly from the compressing device to a traveling grate furnace and progressively passing a bed thereof through the furnace combustion chamber and forcing a draft of air and steam up through the progressively moving bed of compressed masses and sup plying air above the bed to support combustion of the gases formed.

G. The method of utilizing anthracite coal dust and the like in steam boiler and gas producer furnaces of the traveling grate type which comprises, in a continuous opera. tion, compressing the fine fuel into masses of loosely adhering particles, passing these masses directly and continuously from the compressing means to and through the combustion chamber of the furnace and utilizing the compressing means to regulate the quantity of coal dust masses supplied to the furnace.

In testimony whereof, I have sig'ied my name to this specification.

FRANK G. BREYER.

CERTIFICATE 0F CORRECTION.

Patent No. l, 672, 405.

Granted June 5, 1928, a'

FRANK G. BREYER.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as tollovrs: u strike out the words "masses or compressed anthracite bed, the agglomerates ai,

tead "anthracite hed, the agglomerates or compressed masses"; and that ith this correction therein that the sare:

insert ins the said Letters Patent should be read w Page l. lines 90 and 9;

may conform to the record of the case in the Patent Office. Signed and sealed this 3rd day of July, A. D. l92.

(Seal) M. J. Moore,

Acting Commissioner of Patr: 

